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  <!-- portrait-oriented screens that are narrower than 450px will load a cropped image version -->
  <source srcset=",670/-/resize/320x/320.jpg 320w,,670/-/resize/640x/640.jpg 640w,,670/-/resize/450x/450.jpg 450w,,670/-/resize/900x/900.jpg 900w"
          media="(max-width: 450px) and (orientation: portrait)">
  <!-- in the src attribute, specify a fallback image for older browsers that do not support the <picture> tag. here, width of the image is 1000px for the most popular screen width of 1024px -->
  <img src="" 
     srcset=" 320w, 450w, 640w, 750w, 800w, 900w, 1000w, 1200w, 1500w, 16000w, 2000w" 
     sizes="(min-width: 1000px) 50vw, 90vw" 
     alt="Greenpaws the Chameleon">



                img {
  max-width: 100%;

html, body {
  margin: 0;